What route would you go in 2025?
I know you didn't ask my specifically, but I dislike LG so I thought I'd comment anyways...
I would take iOS 18 (yes, even though I will always like iOS 6/10.9 and below) and start adding a bit of color and shapes back into it.
Start with the buttons, add well-defined borders and make the interior color of the button
different than the background. NOT macOS LG's weird floating buttons, which make no sense. They look like cut-out pieces of paper, no depth, yet floating above another piece of paper, with the shadows. It's weird. And not iOS LG's buttons which are semitransparent and hard to read.
macOS LG's buttons are strangely large, the bubble/extreme rounded corners/circlification of the buttons make them feel bloated. Ditto with the weird floating, bordered sidebars. These design decisions are just weird and serve no purpose beyond wasting bits of screen space (which adds up).
Speaking of the background color, make it anything but pure white in light mode, dependent on the content it contains. If the content is buttons, or text bubbles, or most app-UI, the background should not be pure white. It's just a bit too bright. iOS 6 and below's Messages app background was a gray-blue, and OS X's app window backgrounds were slightly gray. The iOS 7/Yosemite+ white backgrounds are too bright and harsh, especially looking at the screen all day.
For icons, I'd really prefer if we went in the opposite direction as Apple wants to go. Instead of bare, one-color, single-symbol icons which are vague, boring, sterile, and lifeless, icons should be expressive, descriptive and unique.